The objectives of the proposed research are: (1) to assess the reliability and validity of the Diagnostic Interview Schedule (DIS) when used in English and Spanish with Hispanics and in English with Anglos; (2) to assess the reliability, validity and utility of the Center for Epidemiologic Studies Depression (CES-D) Scale when used in English and Spanish with Hispanics and in English with Anglos; and (3) to conduct an experiment to assess the effects of language of the interview (Spanish/English) and ethnic status of the interviewer (Hispanic/Anglo) on diagnostic outcomes. Study subjects will consist of four patient samples selected from San Antonio State Hospital: Anglos, monolingual English-speaking Hispanics, monolingual Spanish-speaking Hispanics, and bilingual Hispanics. This latter group will be randomly assigned to English and Spanish interviews. All of the patient groups will be randomly assigned to either a bilingual Anglo or a bilingual Hispanic interviewer to test the ethnic effect. When used by lay interviewers, the DIS will be assessed in the different ethnic/language combinations using (1) test-retest reliability; (2) bias in diagnoses; (3) concordance between lay interviewers and psychiatrist's diagnoses; (4) sensitivity and specificity of the lay interviewers' diagnoses using independent diagnoses by psychiatrists as the criterion; and, (5) credibility (the proportion of false positives when a lay interviewer makes a positive diagnosis). Bias, concordance, sensitivity/specificity, and credibility of the DIS administered by a psychiatrist will also be assessed using as the criterion DSM III diagnoses made by the SASH treatment teams. The CES-D will be assessed using (1) item and scale nonresponse; (2) internal consistency and test-retest reliability; (3) distribution of scale scores; and, (4) sensitivity/specificity using as the criteria the DIS administered by both lay interviewers and psychiatrists and DSM III diagnoses assigned by the SASH treatment teams.